Piperacillin-tazobactam-induced hemophagocytic lymphohistiocytosis in a patient with community-acquired pneumonia: A case report and literature review on diagnostic challenges of elevated procalcitonin

piperacillin-tazobactam can induce HLH, a critical diagnosis requiring immediate drug withdrawal. Elevated PCT in this context is a significant diagnostic pitfall, misleadingly suggesting bacterial infection progression. Unexplained fever and cytopenia during piperacillin-tazobactam therapy - even with elevated PCT - should prompt urgent evaluation for drug-induced HLH. Discontinuation of the causative agent is paramount for recovery and may obviate the need for unnecessary antimicrobial escalation or immunosuppressive therapy.